The general goal of this project is to provide insight into the nature and function of aging memory. The experiments proposed here follow directly from research in our laboratory concerned with a general theme that has driven our work on aging memory for the past two decades: understanding how memory operates as a constructive process that changes with age. Research in both cognitive psychology and neuroscience supports the idea that memory is not a simple recording and reproduction of experience, but instead involves constructive processes that assemble memories from bits and pieces of encoded experiences, often producing accurate memories of past events, but sometimes resulting in errors that illuminate the underlying cognitive and neural operations. Critically, we have recently begun to explore how these constructive processes allow older and younger adults to use memory to imagine or simulate events that might occur in the future or might have occurred in the past. This broad concern with understanding constructive memory and its role in cognitive and neural processes involved in imagining or simulating events guides our hypotheses and experiments. We recently demonstrated that older adults remember their pasts and imagine their futures in less detail than do younger adults. Several experiments will attempt to specify the cognitive processes that underlie these age-related changes in remembering and imagining, and assess whether the age-related deficits can be reduced or eliminated, using a new experimental approach developed recently in our laboratory that should allow us to distinguish between specific age-related changes in memory vs. more general changes in motivation or attention. We will also adapt a previously established experimental paradigm to test the novel hypothesis that older adults have specific problems flexibly recombining elements of past experience, which is critical to constructing event simulations. While our work has focused on how young and old adults simulate possible future events, throughout the adult lifespan people also construct counterfactual simulations of how past events might have turned out differently than they did. Essentially nothing is known about the effects of such simulations on memory in either young or old adults. We propose new procedures to investigate whether and how counterfactual simulations of the past affect memory accuracy in older and younger adults. Understanding how older adults imagine future events may also have important implications for understanding how they carry out intended future actions (prospective memory) and we will perform several experiments using both cognitive and neuroimaging approaches that explore this link. Further, we will also use neuroimaging to examine the effects of aging on the brain networks involved in future planning, using a new paradigm recently established in our lab. We will also use neuroimaging to examine the interaction between memory and attentional control, and the implications of this interaction for event simulation and prospective memory. Overall, the proposed experiments should both deepen and broaden our understanding of how older adults use memory to simulate events and plan for the future.